Hostname: page-component-77c89778f8-cnmwb Total loading time: 0 Render date: 2024-07-19T04:17:23.688Z Has data issue: false hasContentIssue false

Cryo-Em of Large Unilamellar Phospholipid Vesicles That Self- Assemble At a Critical Temperature

Published online by Cambridge University Press:  02 July 2020

T. Talbot
Affiliation:
Division of Bioengineering and Physical Science, ORS, National Institutes of Health, Bethesda, MD, 20892;
F. Booy
Affiliation:
Dep't of Biochemistry, Imperial College, London, SW7 2AY, UK.
R. D. Leapman
Affiliation:
Division of Bioengineering and Physical Science, ORS, National Institutes of Health, Bethesda, MD, 20892;
N. L. Gershfeld
Affiliation:
Division of Bioengineering and Physical Science, ORS, National Institutes of Health, Bethesda, MD, 20892;
Get access

Abstract

The mechanism for assembly of membrane lipid bilayers in vivo is generally considered to occur on existing membranes which act as templates for the assembly process. Not presently understood is the source of the membrane template. A thermodynamic theory describing a spontaneous process for assembly of unilamellar vesicles with properties of a critical state (1,2) has been tested in this study. The spontaneous formation of large unilamellar vesicles (LUV’s) from phospholipid components of cell membranes at a critical temperature T* has now been documented by cryo-electron microscope studies using aqueous dispersions of dimyrystoylphosphatidylcholine (T* = 29°C), and the total lipid extracts of E. coli membranes cultured at 32°C (T* = 32°C). The lipids were incubated at temperatures below, at and above the critical temperatures for LUV assembly. in conformity with thermodynamic theory, and other physical measurements that indicate unique bilayer properties exist at T* (3-5), LUV’s are seen to form only at T*.

Type
Cryoimmobilization, Freeze Substitution and Cryoem (Organized by S. Erlandsen)
Copyright
Copyright © Microscopy Society of America 2001

Access options

Get access to the full version of this content by using one of the access options below. (Log in options will check for institutional or personal access. Content may require purchase if you do not have access.)

References

1.Gershfeld, N. L., Chew. J. Phys., 93, (1989) 5256.CrossRefGoogle Scholar
2.Tajima, K., Koshinuma, M., Nakamura, A., and Gershfeld, N. L., Langmuir, 16 (2000) 2576CrossRefGoogle Scholar
3.Gershfeld, N. L., Mudd, C. P., Tajima, K., and Berger, R. L., Biophys. J. 65 (1993) 1174.CrossRefGoogle Scholar
4.Gershfeld, N. L., and Ginsberg, L., J. Membrane Biol. 156 (1997) 279.CrossRefGoogle Scholar
5.Jin, A. J., Edidin, M, Nossal, R., and Gershfeld, N. L., Biochemistry 38 (1999) 13275.CrossRefGoogle Scholar
6.Gershfeld, N. L., Biochim. Biophys. Ada, Rev. Biomem., 988 (1989)335.CrossRefGoogle Scholar